Hazard-prevention system for a vehicle

ABSTRACT

The invention relates to a hazard-prevention system for a vehicle. The vehicle has devices for sensing driving state variables, for sensing ambient data and for sensing the driver&#39;s activity, and a data processing device. The data processing device is provided for processing the sensed data and for actuating a safety device in accordance with a predefined control strategy. According to the invention, the vehicle has a device for identifying the driver, and the data processing device derives a driver load factor related specifically to the driver from the driving state variables, the ambient data and the data relating to the activity of the driver, and said driver load factor is used to adapt the control strategy.

BACKGROUND AND SUMMARY OF THE INVENTION

The invention relates to a hazard-prevention system for a vehicle havinga device for sensing driving state variables, a device for sensingambient data, a device for sensing the driver's activity, and a dataprocessing device for processing the sensed data and for actuating asafety device in accordance with a predefined control strategy.

Contemporary systems for increasing safety and comfort for the occupantsof a motor vehicle use a number of devices for sensing information. Inparticular, driving state variables, ambient data and, to an increasingdegree, information relating to the vehicle occupants and the driver ofthe vehicle are sensed.

The driving state variables are understood to be variables such asspeed, yaw acceleration, longitudinal acceleration and transverseacceleration, brake pedal setting and accelerator pedal setting,steering angle, the status of operator control elements such as flashingindicator lights and hazard warning lights and the status of sensors andcontrol devices.

Data which is made available by ambient (environmental) sensors,telematic systems and by the vehicle communicating with other vehiclesand fixed communication systems is referred to as ambient data. Examplesof ambient data is information on the current location (for examplewhether the route being travelled on is in a residential area, at theedge of a wood or on a bridge), on the category of road (for examplewhether the road being travelled on is a motorway, a secondary road, asingle-lane road, multilane road with or without oncoming traffic), andon the lane on which the actual vehicle is travelling. Further ambientdata is the state of the road, temperature, weather conditions, lightconditions, ambient noise, air quality and wind conditions, speed,distance, directional movement, type and state of the vehiclestravelling ahead, adjacent vehicles, vehicles travelling behind oroncoming vehicles and of other road users.

Information on the vehicle occupants and the driver are, for example theoccupation of the seats, the weight of the vehicle occupants, the sizeof the vehicle occupants and, in particular, the position of the vehicleoccupants. Sensing the driver's activity also comprises, for exampledetecting the eye movements, the viewing direction but also the operatorcontrol processes of operator control elements such as, for example, theradio, steering wheel, the gear selector lever, brake pedal, mirroradjustment device, air-conditioning system, seat adjustment device,speech-operated control device, navigation module and mobile telephone.

From such information it is possible to infer that the vehicle occupantsare being put at risk or other road users are being put at risk. Systemsfor evaluating this information in order to reduce a risk for theoccupants of motor vehicles are known.

The generic-type-forming German Patent document DE 43 38 244 C2discloses a hazard-prevention system, which has a driving statemonitoring system, a surroundings monitoring system, a driver monitoringsystem and a device for carrying out a hazard-prevention operation. Ahazard situation is determined from the data relating to the movementstate and operating state and the ambient data, and the hazard potentialof said situation is evaluated. If the vehicle is in a hazardoussituation, a decision is made on the basis of the data relating to thestate and action of the driver as to whether the driver has perceivedthe hazardous situation. A hazard-prevention process is carried out onlyif the driver has not perceived the hazardous situation. In order toprevent the hazard, a visual or audible signal is output or anintervention into the vehicle-movement dynamics of the vehicle is made.

In relation to perceiving the hazardous situation, the driver is alsoprovided with other information, for example route information, radioinformation or vocal information. The ability to simultaneously perceivea plurality of information items and rapidly process the perceivedinformation is developed to different degrees in people. Owing to avarying information density during a journey, the driver is subject todifferent load factors depending on the situation. Every driver has anindividual, different load factor which he can cope with, and thus inassociation with this an individual, different perception capability aswell as individual long-term changes and short-term fluctuations in hisability to cope with the load factor and perception capability.Fluctuating abilities to cope with a load factor and varying objectiveload factors can lead to a situation where, given a general warningsystem in which the individual load factor is not taken into account, awarning is issued to the driver too early or too late, and a hazardoussituation is therefore counteracted only to an inadequate degree.

The object of the invention is to reduce the frequency of accidents inmotor vehicles and reduce the severity of accidents. This object isachieved according to the invention by a hazard prevention system havinga device for sensing driving state variables, a device for sensingambient data, a device for sensing the driver's activity, and a dataprocessing device for processing the sensed data and for actuating asafety device in accordance with a predefined control strategy. Thesystem is characterized in that the vehicle has a device for identifyingthe driver, the data processing device derives a driver load factorrelated specifically to the driver which is derived from the drivingstate variables, the ambient data and the data relating to the activityof the driver, and the vehicle has a device for adapting the controlstrategy, which uses the individual driver load factor for this purpose.

The hazard-prevention system for a vehicle contains a device for sensingdriving state variables, a device for sensing ambient data, a device forsensing the driver's activity and a data processing device. The dataprocessing device processes the sensed data and actuates a safety devicein accordance with a predefined control strategy. According to theinvention, the vehicle has a device for identifying the driver.Furthermore, the data processing device derives a measure relatedspecifically to the driver which is characteristic of the instantaneousload factor of the driver from the driving state variables, the ambientdata and the data relating to the activity of the driver. The controldevice adapts the control strategy for actuating the safety device tothe measure of the load factor of the driver. The advantage of thishazard-prevention system of a vehicle is that the driver's safety andcomfort are increased and the safety of the vehicle occupants and ofother road users is increased.

The driver is identified by evaluating vehicle-related variables, thatis to say, for example, data is transferred from the gearbox controlleror engine controller and is used to describe the type of driver(aggressive, nervous, tentative, dynamic). In addition, interventions bythe driver in systems for controlling the dynamics of vehicle movementsuch as ABS (Anti-lock Brake System) ESP (Electronic Stability Program,Driving Stability System), BBS (Brake Boosting System) are sensed andevaluated. Personal features such as the setting of the seat, thesetting of the rear mirror, the setting of the air-conditioning systemor the preferred radio station can be used to identify the driver.Alternatively, the identification of the driver is carried out by meansof a person-related use authorization means (for example key, keyless gocard) or by means of eye recognition, speech recognition, recognition offingerprints).

In one development of the hazard-prevention system, the vehicle has adevice for storing the driver-related history, which contains data whichis characteristic of the respective driver. The data processing deviceuses, in addition to the information specified, the driver-relatedhistory to derive a measure of the load factor of the driver. The devicefor storing the driver-related history senses, in particular, thedriver's activity and creates a history of the driver's activity. Thedriver-related history can additionally contain ambient data and drivingstate variables. It is possible, for example, to assign each driver aroute profile, a speed profile, a specific route which is travelled onregularly and a specific safety distance. In the driver-related historyit is possible to distinguish between a long-term history and ashort-term history. The short-term history contains the characteristicfeatures of the current journey or of another predefined time period,for example, a day. The long-term driver-related history contains thecharacteristic specific features of the driver over a predefinedrelatively long period of time, for example, since the last time theowner of the vehicle changed, since an illness or an accident of thedriver, since the last time the tires were changed or the last serviceor since the driver changed workshop.

By evaluating a history it is detected, for example, whether the currentjourney is a routine journey which is characterized by an accident riskwhich is changed. Furthermore, when evaluating a risk it is possible totake into account any particular strengths, weaknesses andparticularities of the driver. These features relate, for example, tothe attentiveness (reduced during routine journey), perception(relatively uncertain driving style when travelling at night as opposedto day), reaction capability (longer time until the pedal is activated)or the specific capability, for example when simultaneously controllinga plurality of functions (for example driving function, plus navigation,plus mobile radio). An advantage of this development of thehazard-prevention system is that the determination of the degree ofloading on the driver is improved, as a result of which safety isfurther increased in road traffic.

In one embodiment of the hazard-prevention system for a vehicle, thesafety device comprises an information and warning system or is formedby an information and warning system. The processing of the sensed datais carried out by the data processing device in such a way that thoseaction possibilities of the driver which reduce or rule out a hazard aredetermined and that it is checked whether the driver is behaving inaccordance with the determined action possibilities. In addition, it isdetermined whether the measure of the hazard changes rapidly and whetherthis measure lies within predefinable limits. If the measure of thehazard exceeds a predefinable limit, the driver is normally informed, ina first step and/or warned as a function of the severity and the profileof the hazard.

In the following example, the vehicle is travelling with a cruisecontroller with a device for controlling the distance between vehicleson a road with good infrastructure. The driver's activity is sensed andthe reaction capability, the degree of attentiveness, etc. areevaluated. A current driver load factor is derived from this driver datawhich is determined and evaluated, from further individual driver dataand, for example, the ambient data. The time of issuing an informationitem warning to the driver, for example a transfer request which isissued in predefined situations by the cruise control device forcontrolling distance between vehicles, is calculated from this driverload factor. If the driving situation then changes to the effect thatthe driver is to be requested to perform the longitudinal control of thevehicle because the distance from an obstacle is reduced below apredefinable safety distance, the driver will receive a firstinformation item/warning. If there is no reaction from the driver aftera waiting time, which is predefined in particular as a function of thedriver load factor, a second warning will be issued. The warnings can beissued in such a way that the normal reaction of a driver to thesewarnings brings about an action which counteracts the hazardoussituation. Warnings for the driver which are provided for this purposemay address various senses and may be, for example, audible, visual,haptic or olfactory.

As an alternative to or in addition to information/a warning to thedriver, a warning signal can be transmitted to another road user, inparticular to a non-motorized road user. When there is the risk of acollision with a pedestrian, it is possible to generate a noise or alight signal, which is intended to cause the pedestrian to react in away which is suitable to prevent the collision, for example by thepedestrian stopping. The signals can be varied as a function of thehazardous situation, for example a light signal can be changed inintensity, in the flashing frequency, in color and direction. In anothersituation, an acoustic warning signal, for example the squealing of atire can cause a driver of a motor bike to refrain from performing anoriginally planned change in the direction of travel, avoiding acollision between the vehicle and the rider of the motorbike. Thedescribed warning to other road users (partner warning) is carried outaccording to the invention taking into account the individual driverload factor and the possible actions by the driver and/or those actuallycarried out by the driver.

It is also possible to issue a warning to others without taking intoaccount the specific load factor but taking into account the possibleand/or actual actions of the driver. Furthermore, a warning to otherswithout taking into account the specific driver load factor and withouttaking into account the possible and/or actual actions of the driver canbe carried out in order to reduce the probability of an accident or theseverity of an accident. A warning to others for non-motorized roadusers may, for example, sound the horn at a pedestrian in order toprevent him from stepping onto the carriageway or walking into thelikely path of the vehicle on the carriageway onto which he has juststepped.

In another refinement of the hazard-prevention system for a vehicle, thesafety device comprises a system for controlling the dynamics of vehiclemovement. Here, the safety device can comprise exclusively a system forcontrolling the dynamics of vehicle movement or a system for controllingthe dynamics of vehicle movement in conjunction with an information andwarning system, or be formed from these systems. If, with or without aprevious information/warning being issued to the driver, there is nodriver reaction, an inadequate driver reaction or a driver reactionwhich would increase the hazard, the hazard-prevention system intervenesin the vehicle movement dynamics. This may be an intervention in thebrake system, for example emergency braking, an intervention in thevehicle steering system, for example an avoidance maneuver or some otherintervention into the dynamics of the vehicle movement. Such anintervention by the hazard-prevention system can be carried out in orderto avoid an accident and to reduce the severity of an accident. Such anintervention is aborted as soon as there is sufficient driver reactionor a reduction in the hazard below a prescribed value. An example of adriver reaction which leads to an intervention being aborted is theactivation of the brake pedal by the driver during automatic braking. Asa result, the driver assumes responsibility for the braking operationand the automatic braking is terminated.

In a further refinement of the hazard-prevention system for a vehicle,the safety device comprises a vehicle-occupant protection system whichacts on the movement of the vehicle occupant and is intended to make theconsequences of an accident less severe. When there is a predefinedhazard, determined taking into account the driver load factor, thevehicle occupant protection system which acts on the movement of thevehicle occupant is actuated by the hazard-prevention system with orwithout a preceding information/warning function and/or intervention inthe vehicle movement dynamics. Examples of protection systems which acton the movement of a vehicle occupant are conventional restraint systemssuch as airbags and seat belt pretensioners and novel devices forabsorbing energy, in which the hardness and the deformation behavior canbe controlled. Means for preconditioning the vehicle occupants, forexample by adapting the setting of the seat system in accordance withthe hazard, or reversible protection systems, such as electromotive seatbelt pretensioners, are also to be understood as vehicle occupantprotection systems which act on the movement of a vehicle occupant.

After a hazardous situation, in particular an accident, thehazard-prevention system checks whether the driver is exerting controlover the vehicle and whether a further hazard, for example due to apossible secondary collision, is present. The vehicle is, ifappropriate, placed in a safe state (ignition off, fuel supply off,parking brake on, control of the drive) and an automatic emergency callis emitted. The severity of injuries is estimated by means of the sensedparameters and transmitted to the rescue services.

In addition to determining the current driver load factor it is possibleto predict an expected driver load factor from the sensed data, whichfactor is less reliable the longer the prediction time period which isselected. By means of such a prediction, it is possible to specify thetime for the issuing of information/warnings to the driver in such a waythat the gain in safety is as large as possible. For example, aninformation/warning message is brought forward in order to output it ingood time before an expected increased loading on the driver or it isdelayed in order to output it only after a driver load factor which isincreased in the short term. As an alternative or in addition to this itis possible to select a suitable sense for the information/warning, forexample it is possible to output an audible, haptic or olfactorywarning/information when there is a high degree of visual loading on thedriver. When there is a high degree of acoustic loading, a visual,haptic or olfactory warning/information item can correspondingly beissued and/or loading on the driver is reduced by reducing the volume ofthe radio, for example.

There are various possible ways of advantageously configuring theteaching of the present invention. One advantageous embodiment of thehazard-prevention system according to the invention will be described inmore detail below with reference to the drawing.

BRIEF DESCRIPTION OF THE DRAWING

FIG. 1 shows a schematic block diagram of an advantageous embodiment ofthe hazard-prevention system according to the invention.

DETAILED DESCRIPTION OF THE DRAWING

An essential component of the hazard-prevention system is the module fordetermining a driver load factor 101 which, in a simple embodiment,divides the severity of the driver load factor into a plurality ofclasses. An example of the division of the classes are the classes: noload factor, low load factor, medium load factor, increased load factor,high load factor and overloading. In a refined embodiment, the driverload factor is categorized by the module 101 and a load class which hasbeen determined is additionally assigned to one or more load categories.Examples of load categories are: acoustic load, visual load, continuousload, load peak and loading by external influences. In order todetermine the specific driver load factor, information is used from themodule 102 for sensing the driving state variables and the surroundings,the module 103 for observing the driver's activity and vehicle occupantsand the module 104 for identifying the driver. The module 102 forsensing the driving state variables and the surroundings, the module 103for observing the driver's activity and vehicle occupants and the module104 for identifying the driver are connected to a memory 105 forrecording features of the driver which characterize the driver, can beused to identify him or permit the state of the driver to be evaluatedby comparing the stored data with current data. Data for characterizingthe driver are, for example, personal strengths and weaknesses,experience, typologies, medical data, sex and age. Data which can beused for identification are, for example, voice, driver type oroperating pattern and position of adjustment devices such asair-conditioning system, pedals, seat adjustment means, steering wheeland joystick. The module 103 for sensing the driver's activity andobserving the vehicle occupants also senses facial expressions, gesturesand physiological data of the driver and the position and the actions ofthe vehicle occupants and these are used in particular to determine theload on the driver. Further parameters which can be determined by themodule 103 and taken into account in the module 101 are driver fatigue,the condition of the driver, the reaction characteristics and thereaction time of the driver, the driving time and the current speedprofile. To a certain extent special sensors are necessary to sensethese parameters. For example, driver fatigue is determined using aviewing direction recognition means, a means for observing the eyesand/or by sensing the steering angle and the actuation of the pedals.Module 102 registers data on the profile of the route so that, forexample, the journey on a routine route is detected by comparison withthe memory 105.

Data from the memory 105 is additionally used to determine the driverload factor in module 101. In particular, this data relates to thecharacteristics of the driver in similar situations to the situation tobe assessed. If data has been stored about the surroundings or the routeprofile, it is also taken into account in the determination of thedriver load factor.

Module 106 has the function, while taking into account the individualdriver load factor, of informing and warning the driver in such a waythat he prevents the hazardous situation. This takes place, for example,by virtue of the fact that the driver is relieved by the audio volumebeing reduced. Another possible way of adapting the driver warning is toadapt the warning times to the driver load factor, to the type ofdriving and to the perception character of the driver. Furthermore, asense for informing and warning the driver can be selected as a functionof the load factor or of the hazard.

After the warning/information has been issued, the reaction of thedriver to the warning/information is assessed in module 107 and theactions of the driver are evaluated to determine whether he hasperceived the information/warning. For this purpose, a viewing directiondetection means may be used which provides a decision basis for whetherthe driver has perceived a warning or an obstacle. As an alternative orin addition it is possible to carry out the evaluation of the driveractions to determine whether they are suitable for preventing the hazardor making possible consequences of an accident less severe. Theevaluation of the actions and reaction of the driver from module 107 istaken into account in the determination of the driver load factor inmodule 101.

Depending on the result of the evaluation in module 107, module 108brings about a possible intervention into the dynamics of the vehiclemovement, causes protection systems to be actuated and/or causes awarning to be issued to other road users. The protection systems whichcan be actuated may act kinematically or dynamically by a restraintsystem being actuated or by a damping element being activated. It ispossible, for example, for a degree of spring stiffness, a materialproperty, a system pressure or the flow characteristics of a fluid to bechanged for this purpose.

1. A hazard-prevention system for a vehicle, comprising: a device forsensing driving state variables; a device for sensing ambient data; adevice for sensing a driver's activity; a device for identifying aparticular driver; and a data processing device for processing thesensed driving state variables, the sensed ambient data and the senseddriver's activity, and actuating a safety device in accordance with apredetermined control strategy, the data processing device deriving adriver load factor related specifically to the particular driver, thedriver load factor being derived from the sensed driving statevariables, the sensed ambient data, and the sensed data relating to thedriver's activity; and a device for adapting the control strategy, whichutilizes the driver load factor related specifically to the particulardriver for adapting the control strategy.
 2. The hazard-preventionsystem according to claim 1, further comprising: a device for storing adriver-related history containing data characteristic of the particulardriver; and wherein the data processing device additionally uses thedriver-related history to derive the driver load factor relatedspecifically to the particular driver.
 3. The hazard-prevention systemaccording to claim 1, wherein the safety device includes an informationand warning system.
 4. The hazard-prevention system according to claim2, wherein the safety device includes an information and warning system.5. The hazard-prevention system according to claim 1, wherein the safetydevice includes a system for controlling vehicle movement dynamics. 6.The hazard-prevention system according to claim 2, wherein the safetydevice includes a system for controlling vehicle movement dynamics. 7.The hazard-prevention system according to claim 1, wherein the safetydevice includes a vehicle occupant protection system which acts onmovement of an occupant of the vehicle and is designed to lessen theconsequences of accidents.
 8. The hazard-prevention system according toclaim 2, wherein the safety device includes a vehicle occupantprotection system which acts on movement of an occupant of the vehicleand is designed to lessen the consequences of accidents.
 9. Ahazard-prevention system for a vehicle, comprising: a driveridentification device; a processor coupling with the driveridentification device, the processor deriving a driver load factorindividually matched to a particular driver based on driving statevariables, environmental data, and driver activity data; and wherein theprocessor adapts a control strategy for actuating a safety device basedon the derived individual driver load factor.
 10. The hazard-preventionsystem according to claim 9, further comprising a memory storing datahistorically characteristic of the driver; and wherein the processoradditionally uses the stored data to derive the individually matcheddriver load factor.
 11. The hazard-prevention system according to claim9, wherein the safety device comprises an information and warningsystem.
 12. A method for adapting a control strategy for a safety devicein a hazard-prevention system of a vehicle, the method comprising theacts of: sensing driving state variables of the vehicle; sensingenvironmental data related to the vehicle; identifying a particulardriver of the vehicle; sensing the particular driver's activity;deriving a driver load factor individually matched to the particulardriver from the driving state variables, the environmental data and, thedriver's activity; and adapting the control strategy for actuating asaid safety device based on the individually matched driver load factor.13. A software product, comprising a computer readable medium havingstored thereon program code segments that: process driving statevariables for a vehicle; process environmental data related to thevehicle; identify a particular driver of the vehicle; process theparticular driver's activity; derive a driver load factor related to theparticular driver based on the processed driving state variables,environmental data and driver's activity; and adapt a predeterminedcontrol strategy for actuating a safety device utilizing the deriveddriver load factor.